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INTEGRATED APPROACH TO INTEGRATED APPROACH TO TREE DOMESTICATION AND TREE DOMESTICATION AND
CONSERVATION OF CONSERVATION OF
INTEGRATED APPROACH TO INTEGRATED APPROACH TO TREE DOMESTICATION AND TREE DOMESTICATION AND
CONSERVATION OF CONSERVATION OF GENETIC RESOURCES GENETIC RESOURCES
DANIEL OFORI (GRP1 / EA)DANIEL OFORI (GRP1 / EA)ICRAF 23ICRAF 23RDRD AUGUST 2011 AUGUST 2011
Structure of presentation• Introduction• Domestication and conservation strategies
using Milicia sp. as a case study – Field screening– Vegetative propagation – Molecular marker analysis• Seed orchard management
• Discussions/conclusions• Acknowledgements
Introduction
Tree domestication involves accelerated and human-induced evolution to bring species into wider cultivation through a farmer-drivenfarmer-driven or market-ledmarket-led process. This is a science-based and interactive procedure involving the identification, collection, evaluation, production, management and adoption of high quality germplasm
Introduction
Conservation is the management and use of genetic resources so that they may yield the greatest sustainable benefit to the present generation, while maintaining their potential to meet the needs and aspirations of future
Introduction
• By 2050; food, shelter etc will be required for the sustenance of approximately 9 billion people.
• Loss of plants leads to worsening food insecurity, increasing vulnerability to disease and deteriorating social relations
Introduction
• Continued misuse of ecosystems is leading into crisis.
• It is estimated that 60,000 to 100,000 plant species, with diverse economic uses, are under threat of extinction and need to be protected.
Introduction
• Domestication and conservation of species, particularly those which have direct impacts on human well being, have now attained paramount importance, in our efforts to provide for the sustainable utilization of biological resources
• The choice of strategies and tools depends on a clear understanding of the problem and what needs to be achieved.
Objective
The objective of this presentation is to share knowledge and experiences on techniques and tools employed in domestication and conservation of tree genetic resources.
THE IROKO (Mvule) STORY
Milicia sp. (M. Excelsa & M. Regia)
Considered as the most useful species in the family - MORACEAE
Forest condition in Ghana
• Rate of forest depletion 0.7-1.4%• 1.7 m ha out of 8.2 m ha of forest was under
reservation• Over 70% unreserved forest lost over 100 yrs• Solution was forest plantation programme • Target was 20,000 ha/ yr• Good quality planting materials required
Milicia-Phytolyma lata problem
Extraction=172,983 m3 yr-1 ; regeneration = 28,650 m3 yr-1 ; Deficit =144,333 m3 yr-1
Impact of Pest on Plant Growth
Mean growth rate of protected and unprotected Milicia after 18 months
Treat No. ofLeaves
Leaf area(cm2)
Stem dim(cm)
Height(cm)
Unprotected 35.8±4.6 147.0±5.2 1.53±0.12 98.4±6.09
Protected 57.6±9.8 235.9±8.3 2.06±0.18 208.7
Productivity loss of unprotected Milicia after 18 months
Growth variable % mean loss
Height 50.97
Stem diameter 30.73
Foliage 37.84
Leaf area 68.69
Dry biomass 65.93
Screening for pest resistance
133 accessions from 4 Ghanaian provenances
Seedling response to pest attack
Selection of resistant individuals
R
S
S
RS
Trees marked ‘R’ are resistantTrees marked ‘S’ are susceptible
Levels of resistance and Genetic Variation
3 Levels of susceptibility• Resistance• Moderately resistance• Susceptible
Conservation of desirable genotypesStem and root cuttings
Rooted stem cuttings Root cuttings with shoots
Grafting
Collection of scion Grafted plant
Air layering
Ready for planting
Girdled branchWith ball of rootingmedium
In vitro tissue culture
Shoots grown from axillary buds
Ex-situ conservationSerial propagation
Genetic gains from clonal trial at 12 months after establishment
Group % of population Selection
differential
Genetic gain
(G cm)
Percent
gain in
height
Tolerant 39 20.5 4.1 36.7
Susceptible 61 -14.9 -3 -26.7
Molecular DNA characterization
• Distinct morphological differences observed
DNA fingerprinting of Milicia
M. excelsaM. regia
M. excelsaM. regia
RAPD Cluster analysis
Analysis of variance components revealed most of the total variation was among populations (65%)
SV df SS MSS Variance component
% total variation
Among pop
4 96.45 24.12 5.32 65.26
Within pop
15 42.50 2.83 2.83 34.75
Population ID
GD GM GW CD
GM 0.51
GW 0.71 0.46
CD 0.28 0.72 0.94
SW 0.62 0.43 0.31 0.88
Genetic distance among 5 populations
Partitioning of M. regia according the populations
sampled in Ghana and Sierra Leone.
• Accessions of M. regia clustered according to the populations
• Suggesting the need to:1. sample from different
populations2. Conserve different
populations
Species verification
• Chloroplast microsatellite and DNA sequencing at 2 regions– trnL intron– IGS between trnL and trnF
Species verification
Provenances Cytotype1 (Ccmp2-M267)
Cytotype2 (Ccmp2-M275)
Cytotype3 (Ccmp2-M283)
No. of cytotypes in population
GD 0 23 77 2
GM 9.1 90.9 0 2
GW 0 100 0 1
CD 0 0 100 1
SW 0 100 0 1
Cytotype frequency (%) and number of cytotypes in each population. Cytotype 2 is M. regia, and cytotypes 1 and 3 are M. excelsa.
DNA sequence (IGS)
• GDAB1-IGS• CCTAATTATTTATCCTACCTTCTCATTTCGTTAGCGGTTCAAAATTAGTTATCTTTCTCGTT
CATTCTAATTCTACAAACGTATCTGAGCGAAAGTTTTTTTCTTATCACAAGCCTTGTGATATAGATGAAACACGTACAAATGAACATCTTTGAGAAAGGAATCCCAATGTTAAATTTGAATAATTAAAAATTCATTTTATTACTCGTACTGTACTGAAACTTACAAAGTCTTTTTTTTGAAGATCCAAGAAATTCCACCAGGACCTGGATAAGACTTTCCAATCCTCCTTTCGTCTTTTTAATTGACATAGACCCAAGTCCTCTATTAAAATGAGGATGGTGCGTGAGGAATGGTCGGGATACTGAAGAGCA GAGGACTGAA
Colletia ulicina (Rhamnaceae)
Ziziphus ornata (Rhamnaceae)
Ziziphus glabrata (Rhamnaceaea)
Hovenia dulcis (Rhamnaceaea)Schistocarpeae johnsonii(Rhamnaceae)
Ficus pretoriae (Moraceae)
Milicia spp. (GD-AB1)(Moraceae)
Arthocarpus heterophyllus(Moraceae)
Humulus japonicus(Cannabaceae)
Humulus lupulus(Cannabaceae)
Phylogenetic analysis using blast (NCBI)
Plus tree selection
Seed orchard management
Germination percentage
Cedrela seed orchard management
Seed orchard design and management
• Deployment of clones• Pollen contamination
Allanblackia mother block(clone bank)
Quality germplasm= GRP1
CRP7Climate changeAnd agric
GRP 6Multifunctional Landscape (envt. Services)
GRP4 Land healthand restoration
GRP3 Tree product marketing
GRP2 on farmproductivity
CRP4 Agric nutrition and health
GRP5 Climate change
Partners
CRP3. sustainableProduction syt (Food Security)
CRP5 Water, soil& ecosystems
CRP1 Integrated agric. systems
CRP6Forests, trees and AF
Discussion/ conclusion
• Tree domestication & conservation strategies are required for the management of genetic resources for the benefit of humankind today and for future use.
• Effective domestication and conservation require an interplay of several principles, practices and tools.
• The choice of any of these depends on a clear understanding of the problem to be addressed
Discussion & conclusion
• With careful selection of strategies and tools, desired germplasm can be conserved and also made available for planting to combat poverty, food insecurity and provide health care needs, as well as to mitigate climate change, soil degradation, environmental sustainability etc.
Acknowledgements• ITTO• EU• AFORNET• Gov’t Of Ghana
Thank you very muchThank you very muchThank you very muchThank you very much
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